Considering Bowser has been morphed with other beings before like Bowletta, Shrowser, or MegaDragonBowser and morphed with powers into things like Dreamy Bowser, Black Bowser or even Giant Bowser by Magikoopa's magic, it is good to see Nintendo did think of having Bowser transform into Peach already as well. Frankly, that seems like it could have made a really interesting final battle.
But credit to Nintendo's artists, they knew to give Koopa Peach red hair and that a green dress goes best with red hair. That fan version really makes clear how appealing Koopa Peach could be.
In another note of smart fan art, I came across this today.